Baseball/softball bat with shock dissipation characteristics and method of manufacturing same

ABSTRACT

A baseball or softball bat includes a handle having a grip portion adjacent to a first end thereof and a second end disposed within a proximal end of a barrel. The second end of the handle defines a recess having a cross-sectional configuration which is less than the cross-sectional areas of the handle immediately adjacent thereto. A vibration dampening sleeve is disposed over the recess and has an outer surface which engages an inner surface of the proximal end of the barrel. The sleeve may be interlockingly or threadedly engaged to the inner surface of the barrel.

BACKGROUND OF THE INVENTION

The present invention relates to baseball and softball bats. More particularly, the present invention relates to a multi-component bat having shock dissipation characteristics.

Baseball and softball are very popular sports in the United States, Mexico, Cuba, Japan and elsewhere. Due to the competitive nature of these sports, players are constantly seeking ways of improving their performance. An important aspect of baseball and softball is the ability to effectively hit the ball.

Metal, such as aluminum alloy, and composite material bats are allowed in baseball amateur play from Little League to college levels. Such bats are also typically used in slow- and fast-pitch softball. Metal and composite bats are advantageous over wood bats in that they do not break and splinter like wood bats and thus can be repeatedly used with consequent cost savings. Metal and composite bats also have a larger optimal hitting area or power zone than wood bats. Further, the ball comes off a metal or composite bat faster than a wood bat, resulting in longer hits.

However, these bats have certain disadvantages. Bats comprised of metal, composite materials and combinations thereof vibrate upon impact and may send painful vibrations into the hands and arms of the batter if the ball is not hit at the sweet spot of the bat. Various attempts have been made to overcome the vibration problems associated with metal and composite material bats. However, many of these designs are very expensive to manufacture and are prone to structural failure. Also, many of the designs do not effectively dampen the vibrations caused when the bat hits an object, such as a baseball or softball.

Accordingly, there is a continuing need for a bat which is not complex in design and is not expensive to manufacture and not prone to structural failure. Moreover, a bat is needed which effectively dissipates vibrations and shock caused when hitting an object, such as a baseball or softball. The present invention fulfills these needs, and provides other related advantages.

SUMMARY OF THE INVENTION

The present invention resides in a baseball or softball bat having shock dissipating properties and characteristics. The bat of the present invention is a multi-component bat generally comprising a barrel, a handle, and a vibration-dampening sleeve.

The barrel has a proximal end and a distal end. The barrel typically comprises an aluminum or a composite material.

The handle comprises a first end having a grip portion adjacent thereto and a second end defining a recess having a cross-sectional configuration which is less than the cross-sectional areas of the handle immediately adjacent thereto. The recess generally has a concave cross-sectional configuration along a longitudinal axis thereof. The handle may include a tapered portion intermediate the recess and the grip portion. The recess may include a first sloped region and a second sloped region, the first and second sloped regions converging towards an area of smallest cross-sectional area of the recess. The handle may also be comprised of a composite material.

A vibration dampening sleeve is disposed over the recess. The second end of the handle is disposed within the proximal end of the barrel, such that an outer surface of the sleeve engages an inner surface of the proximal end of the barrel. The sleeve may be comprised of an elastic polymer material. The sleeve may be molded onto the recess.

The first sloped region and/or second sloped region of the recess prevents axial movement of the sleeve. In addition, or alternatively, a shoulder adjacent to the recess prevents axial movement of the sleeve. The recess may be configured, such as including projections, to extend into the sleeve, so as to prevent rotational movement of the sleeve as an inner surface of the sleeve generally conforms to the recess.

Preferably, the sleeve and the inner surface of the barrel interlockingly engage with one another, such as the sleeve including projections which interlockingly engage depressions formed on the inner surface of the barrel. The sleeve and the inner surface of the barrel may be threadedly connected to one another.

In accordance with the present invention, a method of creating the baseball or softball bat comprises the steps of providing a barrel having a proximal end and a distal end. A handle is provided comprising a first end having a grip portion adjacent thereto, and a second end defining a recess having a cross-sectional configuration which is less than the cross-sectional areas of the handle immediately adjacent thereto. A sleeve, comprising a material having vibration dampening characteristics, is molded over the recess. The second end of the handle is attached to the proximal end of the barrel such that the sleeve and an inner surface of the barrel engage one another.

Axial movement of the sleeve along the handle is prevented by providing stops bordering the depressed area. Rotational movement of the sleeve is prevented by configuring the recess to extend into the sleeve.

Attaching the handle to the barrel includes the step of interlockingly engaging the sleeve with an inner surface of the barrel. This may comprise molding a sleeve having projections which matingly engage depressions formed on an inner surface of the barrel. The sleeve may be threadedly engaged with an inner surface of the barrel.

Other features and advantages of the present invention will become apparent from the following more detailed description, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings illustrate the invention. In such drawings:

FIG. 1 is a partially fragmented, cross-sectional view of a baseball or softball bat embodying the present invention;

FIG. 2 is a partially fragmented, exploded perspective view of component pieces of a bat embodying the present invention;

FIG. 3 is a partially fragmented side perspective view of an end of a handle of the bat having a recess;

FIG. 4 is a perspective view similar to FIG. 3, but illustrating a vibration dampening sleeve disposed over the recess, in accordance with the present invention;

FIG. 5 is a cross-sectional view of the sleeve disposed over the recess of the handle, in accordance with the present invention;

FIG. 6 is a cross-sectional view similar to FIG. 5, but illustrating projections of the recess extending into the sleeve;

FIG. 7 is a perspective view of a mold exploded away from the recessed area of the handle, in preparation of molding a vibration dampening sleeve thereon, in accordance with the present invention; and

FIG. 8 is an enlarged sectional view of area “8” of FIG. 1, illustrating the interconnection of the barrel and the handle and sleeve, in accordance with the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

As shown in the accompanying drawings, for purposes of illustration, the present invention resides in a multi-component baseball or softball bat and a method for manufacturing the same. The baseball bat, generally referred to by the reference number 10, has shock dissipation characteristics, an enlarged hitting zone, and sound control.

With reference now to FIG. 1, a cross-sectional view of a bat 10 embodying the present invention is illustrated. The bat 10, as illustrated in FIGS. 1 and 2, generally comprises a barrel 12, a handle 14, a vibration dampening sleeve 16 attached to the handle 14 and the barrel 12. The sleeve 16 provides sound control and shock and vibration dissipation to the bat 10. The incorporation of the sleeve 16 and the design of the barrel 12 also provide an enlarged hitting zone or “sweet spot” of the bat 10.

The barrel 12 is typically comprised of aluminum or a laminate composite material, such as composite fibers or sheets, which may be pre-impregnated with resins and the like. Typically, as illustrated in FIGS. 1 and 2, the barrel 12 is generally hollow. The barrel has a proximal end 18 which is typically tapered inwardly, as shown. At a generally opposite end of the bat is a distal end 20. The distal end 20 may have a plug 22 attached thereto so as to close the open distal end 20 of the barrel 12. Alternatively, the distal end 20 of the barrel 12 may be closed in upon itself so as to close the open distal end 20, as is known in the art. However, the open distal end 20 of the barrel 12 is not closed until the handle 14 has been inserted therethrough, as will be more fully described herein.

With continuing reference to FIGS. 1 and 2, the handle 14 is also typically comprised of a laminate composite material. The handle 14 includes a first end 24 having a grip portion 26 adjacent thereto. The grip portion 26 of the handle 14 is typically of a generally consistent cross-sectional diameter. However, the handle 24 includes a tapered section 28 which tapers outwardly from the grip portion 26 towards a second end 30 of the handle 14, which is typically larger in cross-sectional configuration and area than the grip portion 26 of the handle 14.

With reference now to FIG. 3, the second end of the handle 30 defines a recess 32 having a cross-sectional configuration which is less than the cross-sectional areas of the handle 14 immediately adjacent thereto. In one configuration, as illustrated, the recess 32 includes a first sloped region 34, which slopes downwardly from the tapered portion 28 of the handle 14. The recess 32 may further include and be defined by a second sloped region 36, spaced apart from the first sloped region 34. As can be illustrated in the various figures, including FIG. 3, the first and second sloped regions 34 and 36 decline and converge towards an area of smallest cross-sectional area 38 of the recess 32. As can be seen in FIG. 5, the recess 32 has a generally concave cross-sectional configuration along a longitudinal axis of the recess 32 and handle 14.

With reference now to FIGS. 2 and 4-6, the sleeve 16 is disposed over the recessed area 32 of the handle, as illustrated in FIGS. 4-6. The sleeve is configured such that an inner surface thereof generally conforms to the outer surface of the recess, as illustrated in FIGS. 5 and 6. The sleeve is comprised of a material having vibration dampening and dissipating characteristics. The sleeve 16 typically is comprised of an elastic polymer material having a durometer hardness of between 25-100 Shore A. For example, the sleeve 16 may be comprised of an elastic polymer material.

The sleeve 16 is securely locked in place at the recess 32 of the handle 14. Stops may be provided bordering the recess to prevent axial movement of the sleeve 16. The first sloped portion 34 and/or the second sloped portion 36 can serve as stops and prevent axial movement of the sleeve 16. As the recess 32 is generally concave in configuration, the conforming inner surface of the sleeve 16 is generally convex, so as to conform and generally mate with the recess 32. The concavity of the recess 32 and the convex configuration of the inner surface of the sleeve 16 create a male-female engagement, with the first and second slopes 34 and 36 serving to prevent axial movement of the sleeve 16. Addition of stops may be incorporated into the handle 14, such as the illustrated ring 40 which defines a shoulder 42 which engages an end 44 of the sleeve 16.

The recess 32 may also be configured such that portions of the recess 32 extend into the sleeve 16. This may be, for example, by using projections, such as the illustrated ribs 46 which project outwardly from the recess 32 and which extend into the elastomeric sleeve 16. These projecting ribs 46 extend into the sleeve 16, as illustrated in FIG. 6, and prevent rotational movement of the sleeve 16.

Although the sleeve 16 may comprise a separate, generally tubular, component which is physically positioned and disposed over the recessed area 32 of the handle 14 and secured in place by virtue of the configuration of the recess and stops described above, or even adhered into place, preferably, the sleeve 16 is molded onto the recess 32. Referring now to FIG. 7, a mold 48 and 50 is placed over the recessed portion 32 of the handle 14. An injection needle 52 is inserted into aperture 54 of the mold 48 and 50 so as to inject the elastic polymer material forming the sleeve 16 into the mold 48 and 50. By way of example, the mold components 48 and 50 may be comprised of steel, which is preheated to approximately 60° C. The projecting rib 46 extending from the recessed area 32 provides a secure assembly of the sleeve 16 and handle 14 after formation and molding of the sleeve 16. Alternatively, the mold can also be made with recessed slots as an option to provide a solid locking between the handle 14 and its later formed elastic polymer sleeve 16.

A liquid elastic polymer material is injected into the mold 48 and 50 to form a concave-convex shaped sleeve 16, as illustrated and described above, and form a shell around the outer surface of the recessed area 32 of the larger second end 30 of the handle 14. The newly injected elastic polymer is cured at approximately 140° C. under a pressure of approximately 70 Mpa for approximately ten to twenty minutes. The temperature of the mold is reduced to approximately 60° C., and mold members 48 and 50 are removed from the handle 14, resulting in the newly formed vibration dampening sleeve 16 molded thereon, as illustrated in FIGS. 4-6. Molding the sleeve 16 onto the recessed area 32 of the handle 14 is considered a preferable method of creating the bat 10 of the present invention as the molded vibration dampening sleeve 16 will conform to the recessed area 32 and the aforementioned locking components and aspects of the handle 14.

The method of installing the various components of the bat 10 will now be described. A thin layer of adhesive 56 is applied onto an inner surface of the barrel 12 at the proximal end 18 thereof. A thin layer of adhesive may also be applied on the outer surface of the vibration dampening sleeve 16. It will also be appreciated that the adhesive may be applied to only the outer surface of the sleeve 16 or only the inner surface of the proximal end 18 of the barrel 12. The first end 24 of the handle 14 is inserted through the open distal end 20 of the barrel 12 until the outer surface of the vibration dampening sleeve 16 engages the inner surface of the proximal end 18 of the barrel 12, as illustrated in FIGS. 1 and 8.

In a particularly preferred embodiment, the sleeve 16 interlockingly engages the inner surface of the proximal end 18 of the barrel 12. This may be done by virtue of creating either projections or recesses on the outer surface of the sleeve 16 during its molding process which mate and interlock with corresponding projections or recesses formed on the inner surface of the barrel 12. In the illustrated embodiment, projections 58 comprising external threads are formed on the sleeve 16 during its molding process, which engage internally formed threads or corrugations 60 formed in the inner surface of the proximal end 18 of the barrel 12, such that the external threads 58 are moved into the internal threads 60, such as by twisting or rotating the handle 14 so as to make a threaded connection between the vibration dampening sleeve 16 and the barrel 12. The entire bat assembly is then left at room temperature or in an oven with elevated temperature for curing.

Referring again to FIGS. 1 and 2, to finalize the bat 10, a knob 62 may be attached to the first end 24 of the handle 14 and the plug 22 inserted into the enlarged open distal end 20 of the barrel 12, if necessary. The exterior of the bat can then be painted, have appliqués or labels placed thereon, a grip placed over the grip portion 26 of the handle 14, etc. to complete the bat.

When a ball is hit by the barrel 12 of the bat 10, vibrations generated by the forceful impact of the ball will be transmitted to the vibration dampening and dissipating sleeve 16 in contact with the inner surface of the proximal end 18 of the barrel 12, instead of the handle 14. This provides many advantages, including increased comfort in using the bat for the batter as the shock and vibrations will not be imparted, or are greatly reduced, to the grip portion 26 of the handle 14. The sleeve 16 acts as both a connecting means between the handle 14 and the barrel 12 as well as serving as a vibration and shock dampening means. Furthermore, the sleeve 16 imparts an improved sound characteristic to the bat 10, which would otherwise have a very unnatural sound upon hitting a ball, as compared to a traditional wood bat. Furthermore, it has been found that the “sweet spot” or hitting zone of the barrel 12 is enlarged by this arrangement.

Although several embodiments have been described in detail for purposes of illustration, various modifications may be made without departing from the scope and spirit of the invention. Accordingly, the invention is not to be limited, except as by the appended claims. 

What is claimed is:
 1. A baseball or softball bat, comprising: a barrel having a proximal end and a distal end; a handle comprising a first end having a grip portion adjacent thereto, and a second end disposed within the proximal end of the barrel and defining a recess having a cross-sectional configuration which is less than the cross-sectional areas of the handle immediately adjacent thereto; and a vibration dampening sleeve disposed over the recess and having an outer surface which engages an inner surface of the proximal end of the barrel.
 2. The bat of claim 1, wherein an inner surface of the sleeve generally conforms to the recess.
 3. The bat of claim 1, wherein the recess has a generally concave cross-sectional configuration along a longitudinal axis thereof.
 4. The bat of claim 1, wherein the recess includes a first sloped region.
 5. The bat of claim 4, wherein the recess includes a second sloped region, the first and second sloped regions converging towards an area of smallest cross-sectional area of the recess.
 6. The bat of claim 5, wherein at least one of the first sloped region or second sloped region prevents axial movement of the sleeve.
 7. The bat of claim 1, wherein the handle includes a tapered portion intermediate the recess and the grip portion.
 8. The bat of claim 1, wherein the handle includes a shoulder adjacent to the recess preventing axial movement of the sleeve.
 9. The bat of claim 1, wherein the sleeve includes projections which interlockingly engage depressions formed on the inner surface of the barrel.
 10. The bat of claim 1, wherein the sleeve and the inner surface of the barrel are threadedly connected to one another.
 11. The bat of claim 1, wherein the sleeve is comprised of an elastic polymer material.
 12. The bat of claim 1, wherein the sleeve is molded onto the recess.
 13. The bat of claim 1, wherein the recess includes projections extending into the sleeve.
 14. The bat of claim 13, wherein rotational movement of the sleeve is prevented by the projections of the recess.
 15. The bat of claim 1, wherein the barrel and the handle are comprised of a composite material.
 16. A method of manufacturing a baseball or softball bat, comprising the steps of: providing a barrel having a proximal end and a distal end; providing a handle comprising a first end having a grip portion adjacent thereto, and a second end defining a recess having a cross-sectional configuration which is less than the cross-sectional areas of the handle immediately adjacent thereto; molding a sleeve comprised of a material having vibration dampening characteristics over the recess; attaching the second end of the handle to the proximal end of the barrel such that the sleeve and an inner surface of the barrel engage one another.
 17. The method of claim 16, wherein the attaching step includes the step of interlockingly engaging the sleeve with an inner surface of the barrel.
 18. The method of claim 17, wherein molding step comprises molding a sleeve having projections which matingly engage depressions formed on the inner surface of the barrel.
 19. The method of claim 16, wherein the attaching step includes the step of threadingly engaging the sleeve and an inner surface of the barrel.
 20. The method of claim 16, wherein the providing steps comprise providing a barrel and a handle comprised of a composite material.
 21. The method of claim 16, including the step of preventing axial movement of the sleeve by providing stops bordering the recess.
 22. The method of claim 16, including the step of preventing rotational movement of the sleeve by configuring the recess to extend into the sleeve. 